1. Field of the Invention
The present invention is directed to apparatus for conditioning tobacco, and more particularly to an apparatus for treating tobacco with a gas.
2. Description of the Prior Art
It is well known to condition tobacco with a gas in order to, for example, cool tobacco, heat tobacco, or moisturize tobacco.
The following U.S. patents are exemplary of the prior art.
U.S. Pat. No. 187,187 issued on Feb. 6, 1877 shows one such apparatus which has an inclined rotating drum having a tobacco inlet at the elevated end in order to separate particulate material from the treating gas. An atomizing nozzle is located at the lower end of the drum to direct a stream of tobacco treating material such as steam or into the tobacco out end of the drum to pass in counter-current flow to the tobacco through the drum.
U.S. Pat. No. 436,032 shows an apparatus for treating tobacco which includes an inclined, hollow drum having a tobacco feed tube located at the elevated end and a tobacco discharge opening at the lower end. The drum has a plurality of longitudinally extending hollow perforated blades. Tobacco is introduced into the drum through the feed tube and is tumbled as it moves in the drum toward the discharge opening. A treating gas is introduced into the hollow blades, and exits the hollow blades through the perforations to contact the tumbling tobacco therein.
U.S. Pat. No. 483,401 shows an apparatus for preparing tobacco which includes a hollow (rotatable) cylinder provided with screw flanges with a tobacco inlet opening at one end. THe end of the cylinder opposite the tobacco inlet end is formed as a converging funnel. A plurality of pens extend generally radially into the converging funnel. The end of the funnel is open to provide an outlet for treated tobacco. A steam nozzle is located at the tobacco inlet end of the cylinder to inject tobacco treating steam into the cylinder in concurrent flow with the flow of tobacco through the cylinder.
U.S. Pat. No. 687,308 shows another apparatus for treating tobacco which having an inclined rotatable cylinder or drum having a plurality of pens radially projecting inwardly. Tobacco to be treated is introduced into the cylinder at its lower end along with a treating gas. The elevated upper end has a screen for separating particulates from the gas stream.
U.S. Pat. No. 2,799,278 shows a system for treating tobacco which includes an inclined rotating cylinder which has radially inwardly projecting pins. Tobacco to be treated is introduced into the elevated end of the cylinder, and a nozzle injects steam into the elevated end of the cylinder. As the tobacco and steam move from the elevated end to the lower end of the cylinder, the tobacco is softened by the steam and action of the pins projecting from the cylinder walls.
U.S. Pat. No. 3,409,025 shows an apparatus for treating tobacco which includes an inclined rotatable cylindrical drum which has an open tobacco inlet at its elevated end and an open tobacco outlet at its lower end. A heated air nozzle is located at the elevated tobacco inlet to direct heated air into the drum in concurrent flow with the flow of tobacco through the drum. The drum includes heating coils which extend in a longitudinal direction of the drum. The heating coils function to heat the tobacco within the drum as well as to act as blades to agitate the tobacco moving from the elevated end to the lower end of the drum.
U.S. Pat. No. 3,760,816 shows an apparatus for conditioning tobacco which includes an inclined, rotatable drum having a tobacco inlet at the elevated end and a tobacco outlet at the lower end. A hood is located over the elevated end and is connected to an exhaust fan. Treating gas is introduced at the lower tobacco exit end to introduce treating gas into the drum in counter-current flow to the flow of tobacco being treated. The drum is also equipped with heating coils which extend longitudinally of the drum. The coils function to heat the tobacco as well as tumble the tobacco.